Documentation

pkmodel is a Pharmokinetic modelling library.

It contains functionality for creating, solving, and visualising the solution of Parmokinetic (PK) models

Classes

AbstractModel.py: Abstract class for 1st Order Linear ODE for pharmokinetic model

class pkmodel.AbstractModel.AbstractModel

abstract solve() → pkmodel.AbstractSolution.AbstractSolution

Abstract class for 1st Order Linear ODE for pharmokinetic model

Raises

NotImplementedError – Must be implemented by subclasses.

AbstractProtocol.py: Abstract class for 1st Order Linear ODE for pharmokinetic model

class pkmodel.AbstractProtocol.AbstractProtocol

abstract generate_model() → pkmodel.AbstractModel.AbstractModel

Generates 1st Order linear ODE pharmokinetic model from input arguments that define model protocol.

Raises

NotImplementedError – Must be implemented by subclasses.

AbstractSolution.py: Abstract class for solution of 1st Order Linear ODE for pharmokinetic model

class pkmodel.AbstractSolution.AbstractSolution

abstract property get_solution

Returns linear approximate solution of Model, computed with scipy ivp

Raises

NotImplementedError – Must be implemented by subclass

Dose functions defining the dosing regimens of pharmokinetic model.

members

inherited-members

class pkmodel.protocol.Protocol(file_dir=None)

Protocol object which initialises the Model based on the input parameters and default parameters

Args:

AbstractProtocol (Class): AbstractProtocol is super-class of Protocol.

call_all_checks()

Calls all the check functions at once

check_fill_parametersCLX()

Checks that parameters CL and X are floats and larger than 0

Raises:

TypeError: If CL or X is not a float ValueError: If CL or X is less than 0

check_fill_parametersdict()

Checks the parameters are a dictionary

Raises:

TypeError: If parameters are not a dictionary

check_fill_parametersint()

Checks that nr_compartments and time paramters are integers

Raises:

TypeError: If nr_compartments or time are not an integer ValueError: If nr_compartments or time are less than 0 ValueError: If time is larger than 5

check_fill_parametersperip()

Checks that periph_* parameters are a tuple with two floats both larger than 0.

Raises:

TypeError: If periph_* parameter is not a tuple TypeError: If a value in the tuple is not a float ValueError: If a value in the tuple is less than 0

check_fill_parametersstr()

Checks the name and injection_type parameters are strings

Raises:

TypeError: If the name and injection_type parameters are not strings

fill_parameters(file_dir)

Fills the parameters using the config file and updates the default values based on these values

Args:

file_dir (string): Relative path for the config file

generate_model()

Generates a model object based on the parameters in the Protocol object

Raises:

Exception: If an incorrect mode is given (not intravenous nor subcutaneous)

Returns:

Model Obnject: An initiated model using the defined parameters

read_config(file_dir)

Reads in config file and converts into python dictionary

Args:

file_dir (string): Relative path for the config file

Returns:

dict: Dictionary of the parameters

models.py contains Model baseclass and Intravenous and Subcutaneous model subclasses.

return

solution to PK ODE Model

rtype

Solution object

class pkmodel.models.IntravenousModels(parameters)

Class for the intravenous bolus model with a single central compartment and variable number of peripheral compartments

generate_transition(parameter_tuple, q_central, q_peripheral)

Helper function computes single transition equation describing flux between central compartment and single peripheral compartment.

Parameters

• parameter_tuple (tuple of non-negative floats) – (V_peripheral, Q_peripheral) - tuple containing volume and rate constants that define a peripheral compartment

• q_central (float) – time variable amount q in central compartment solved numerically at time t

• q_peripheral (float) – time variable amount q in peripheral compartment solved numerically at time t

Returns

computed transition value describing flux between central and peripheral compartment at time t

Return type

float

rhs(t, y)

Right Hand Side (rhs) of the ODE model. Contains the implementation of the differential equations defining the PK model.

dq_c / dt = Dose(t) - (q_c / V_c) * CL - Q_px( q_c / V_c - q_px / V_px)

dq_px / dt = Q_px(q_c / V_c - q_px / V_px)

Called as lambda function within scipy solve_ivp.

Parameters

• t (float) – current time point

• y (array of float) – [q_c, q_p1, …, q_pn] - current amount in compartment at time point t with dimensions N where N is total number of compartments

Returns

dq_dt - an array of all compartments’ dq_dt values at time t with dimensions N where N is total number of compartments

Return type

array of float

solve()

Function computes the numeric solution of the PK ODE model with scipy solve_ivp for a specified time interval.

Returns

numeric solution of amount for each compartment as float array with dimensions N x T, where N is the total number of compartments and T is the length of the time eval vector.

Return type

Solution

class pkmodel.models.Model(parameters)

Base model for PK 1st order linear ODE model with variable number of peripheral compartments.

Parameters

parameters (dict) – parameters and constants of the model

generate_transition(parameter_tuple, q_central, q_peripheral)

Helper function computes single transition equation describing flux between central compartment and single peripheral compartment.

Parameters

• parameter_tuple (tuple of non-negative floats) – (V_peripheral, Q_peripheral) - tuple containing volume and rate constants that define a peripheral compartment

• q_central (float) – time variable amount q in central compartment solved numerically at time t

• q_peripheral (float) – time variable amount q in peripheral compartment solved numerically at time t

Returns

computed transition value describing flux between central and peripheral compartment at time t

Return type

float

solve()

Function computes the numeric solution of the PK ODE model with scipy solve_ivp for a specified time interval.

Returns

numeric solution of amount for each compartment as float array with dimensions N x T, where N is the total number of compartments and T is the length of the time eval vector.

Return type

Solution

class pkmodel.models.SubcutaneousModels(parameters)

Class for the subcutaneous injection model with a single central compartment, a single absorption compartment, and variable number of peripheral compartments

generate_transition(parameter_tuple, q_central, q_peripheral)

Helper function computes single transition equation describing flux between central compartment and single peripheral compartment.

Parameters

• parameter_tuple (tuple of non-negative floats) – (V_peripheral, Q_peripheral) - tuple containing volume and rate constants that define a peripheral compartment

• q_central (float) – time variable amount q in central compartment solved numerically at time t

• q_peripheral (float) – time variable amount q in peripheral compartment solved numerically at time t

Returns

computed transition value describing flux between central and peripheral compartment at time t

Return type

float

rhs(t, y)

Right Hand Side (rhs) of the ODE model. Contains the implementation of the differential equations defining the PK model.

dq0 / dt = Dose(t) - k_a * q_0

dq_c / dt = k_a * q_0 - (q_c / V_c) CL - Q_px( q_c / V_c - q_px / V_px )

dq_px / dt = Q_px (q_c / V_c - q_px / V_px)

Called as lambda function within scipy solve_ivp.

Parameters

• t (float) – current time point

• y (array of float) – [q_0, q_c, q_p1, …, q_pn] - current amount in compartment at time point t with dimensions N where N is total number of compartments

Returns

dq_dt - an array of all compartments’ dq_dt values at time t with dimensions N where N is total number of compartments

Return type

array of float

solve()

Function computes the numeric solution of the PK ODE model with scipy solve_ivp for a specified time interval.

Returns

numeric solution of amount for each compartment as float array with dimensions N x T, where N is the total number of compartments and T is the length of the time eval vector.

Return type

Solution

” Solution.py: Class implementation for Solution of 1st Order ODE for pharmokinetic model

class pkmodel.solution.Solution(solution_vector, parameter_dict)

Parameters

AbstractSolution ([type]) – [description]

generate_plot()

Generate solution vector plots

Returns

plots of quantity vs time for each compartment

Type

matplotlib plot

property get_parameters

Return parameter dictionary

:return dictionary of paremters :type: dict

property get_solution

Return list of y and t arrays from solution vector

Returns

list of y, t –> where y = np.array of quantities and

<– t = np.array of time :rtype: list of numpy arrays

output()

creates and populates output directory <– with saved plot, parameters, and solution

Returns

None

save_parameters(dir_path, model_no)

saves input parameters in text file

Returns

None

save_plot(dir_path, model_no)

saves plot of solutions as png

Returns

None

save_solution(dir_path, model_no)

saves solutions in a csv file

Returns

None

show_plot()

displays plot for testing

Returns

None